CPU fan running to fast

I switched the motherboard on my HP Pavillion a4316f, AMD Athlon II 620 Quad Core, 6GB DDR3, Win 7 Home Premium, New motherboard Asus M4A88TD-M/USB3. I notice the new motherboard had 4 pins for CPU fan but im still able to connect the 3 with my current cpu fan its compatible but the fan is running fast at all times and very loud. I tried changing the fan speed since the new motherboad comes with software to adjust fas speed but it wont slow down running at over 6400 rpm

Heatsink is installed correctly I think it has to do with it been a 3 pin instead of the 4 pin, I dont think the board is bad brand new and if it was bad i dont think it would boot, Thanks for the input

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